Anti – inflammatory and antioxidant effects of Tetrapleura Tetraptera (Schumach & Thonn.) taub. fruit extract in Carrageenan/Kaolin-induced acute monoarthritis in rats

Background: Tetrapleura tetraptera has been reported traditionally for the treatments of various ailments, which include convulsion, leprosy, inflammation and rheumatic pains, schistosomiasis, asthma and hypertension. The antiinflammatory activity of the aqueous extract of T. tetraptera fruit in egg albumin-induced paw oedema as well as in vitro anti-inflammatory and antioxidant activity had been documented. However, there had been no studies on the antiarthritic properties of the plant.Objectives: The present study was designed to investigate in vivo anti-inflammatory and anti-oxidant activities of the methanol extract Tetrapleura tetraptera in carrageenan/kaolin-induced acute monoarthritis in rat.Materials and methods: The acute toxicity of the methanol plant extract was determined using Lorke’s method. In vivo carrageenan/kaolin induced arthritis assay was performed on Tetrapleura tetraptera (TtME) extract (100, 200 and 400 mg/kg) using albino rats. Indomethacin (10 mg/kg) and normal saline were employed as positive and negative controls, respectively. Histological study was performed on the knee joint of the animals after collection of blood for antioxidants analysis.Results: Acute toxicity study showed that TtME is safe by oral administration up to 5000 mg/kg body weight. Oral administration of TtME and indomethacin (10 mg/kg) produced a significant (p < 0.05) time and dose-dependent decrease in joint diameter. There was a decrease in malondialdehyde and increase in glutathione and superoxide dismutase. The histological assessment revealed no major adverse effects on the animals.Conclusion: Tetrapleura tetraptera fruit extract possesses anti-arthritic activity, which may be attributed to its antiinflammatory and antioxidant activity.Keywords: Tetrapleura tetraptera, Antioxidant, Anti-inflammatory, Anti-arthritic activity, Histopatholog